1. Field of the Invention
The present invention relates to an on-board camera system which monitors the area around a vehicle.
2. Description of Related Art
Conventionally, in order to display an image obtained by capturing the area around a vehicle on a display device provided in the vehicle, a vehicle periphery monitoring device is known which monitors an area around a vehicle and which includes a camera that captures an area around a vehicle, a display device provided in the vehicle, and image processing means for encoding or decoding the image data captured by the camera using a wavelet transform. In recent years, in order to acquire peripheral information, the mounting of an on-board camera system, which uses a moving image, in vehicles is increasing. According to such an on-board camera system, in a situation in which the left and right sides of an intersection that a driver is approaching are not visible due to obstacles on the left and right sides of the driver's seat, an image in front of the vehicle is displayed on the display device so that the conditions at the intersection can be checked (for example, refer to JP-A-2005-303450 (Patent Document 1)).
Incidentally, in a front or rear monitoring device of a vehicle which uses an on-board camera system, it is desirable to be able to change the angle of view of an image captured by a camera since a region to be monitored changes with an object to be monitored. For example, it is desirable to obtain an image of a narrow angle of view in order to recognize preceding vehicles, obstacles, signs, and the like in distant places, while it is desirable to obtain an image of a wide angle of view in order to recognize vehicles traveling in parallel, obstacles, pedestrians, signs, and the like in the vicinity.
However, if two cameras are provided in order to obtain images corresponding to at least two angles of view, there is a problem in that it is not practical since the cost of the system is increased. In order to solve such a problem, a device for monitoring the outside of a vehicle capable of imaging an object accurately in a wide distance range from short distances to long distances while reducing the number of imaging elements is known (for example, refer to JP-A-2010-271429 (Patent Document 2)). This device for monitoring the outside of a vehicle includes an imaging lens system for long distances and an imaging lens system for short distances in order to acquire images of different angles of view.